The RMT union's complaints relate to the transfer of Piccadilly Line control-room services to a new centre in Hammersmith.
Transport for London plans to replace a number of separate control centres with a single one from 2017.
The Rail, Maritime and Transport Union says the move will cause job losses - and that there are also issues with rates of pay and the lack of "any meaningful offer for Service Control staff for the Olympic period."
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Aydin Onac has been suspended from his role at St Olave's Grammar School in Orpington.
Leaders of the Aslef union are recommending that their members accept the deal.
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